Printing is a common method for selectively depositing a functional material on a substrate. The functional material needs to be formulated with other materials before the functional material can be printed on a substrate. Since a formulation is typically formed by dispersing the functional material in a solvent or liquid, the formulation is is generally wet. Thus, the formulation is often referred to as an ink or paste, depending on the viscosity.
Whether it is an ink or a paste, a formulation typically includes certain additives intended to make the printing process easier and more reliable, but those additives may also interfere with the properties of the functional material. For example, when depositing biological materials, the presence of additives and even artifacts of the deposition process, such as high temperature, can render the biological material inactive. Thus, if the additives within the formulation do not substantially interfere with the intended functions of the functional material to be deposited, the additives can stay in the functional material; otherwise, the additives must be removed from the functional material.
The present disclosure provides an improved method for depositing a functional material on a substrate.